The present invention relates to alarm systems, and more particularly to an alarm system that provides proximity detection in combination with vocal warnings generated electronically, e.g., by voice synthesis techniques. The alarm system advantageously senses any unauthorized approach towards a protected object, such as an automobile, motorcycle, or house, and vocally warns the person making the unauthorized approach to back away from the object before an alarm is sounded.
Alarm systems are known in the art. A typical alarm system is installed for the purpose of securing a defined area from unauthorized intrusion or trespass. The defined area that is secured by the alarm system will usually comprise a closed area, such as a specified room(s) within a building, or an entire building or house. In the case of automobile alarm systems, the secured area protected typically comprises the interior of the automobile, and may also extend to unauthorized tampering with the exterior of the automobile. However, no known systems extend to protecting an area or zone around a mobile object, such as vehicle; and of warning someone who intentionally or unintentionally enters this protected zone prior to sounding the alarm.
All alarm systems have certain basic elements in common. All include one or more sensors that are used to sense an entry event or other activity that could be viewed as an unauthorized tampering or presence (hereafter a "violation"). The sensor(s) are coupled, usually with electrical wires (although RF or other communication links may also be used), to a central control unit or equivalent circuit. When an entry or other activity is sensed by the sensor, an appropriate signal is sent to the control unit, which, if armed, generates an alarm signal. The alarm signal, in turn, may be used locally to sound an audible alarm, such as a loud siren or loud bell (intended to scare off the would-be intruder and to draw attention to the fact that an intrusion or other violation has been detected). The alarm signal may also be used to signal a remote location, such as a police station or a neighboring facility, of the violation that has been detected.
In the case of a simple automobile alarm system, the vehicle's existing electrical system (used, for example, to turn on a light when a door is opened) is used as a basic sensor that is connected to a control module. An alarm circuit within the control module is triggered whenever the monitored event occurs, such as when the door is opened. A siren or horn is sounded if too much time passes (typically 10 to 15 seconds) before the alarm system is turned off (disarmed).
More sophisticated automobile alarm systems supplement this basic alarm system with additional sensors (e.g., that sense the opening of the hood or trunk, the removal of an automobile cover, or the presence of "motion" within the vehicle) and a correspondingly more complex control module. Such systems may also include backup battery protection and remote paging capabilities. Further, it is not uncommon for such systems to take more preventative steps than merely sounding an alarm. For example, automobile alarm systems are known in the art that, upon sensing a violation (such as the opening of the door, trunk or hood while the system is armed), will disable the ignition and/or fuel delivery system of the automobile's engine, thereby rendering it impossible to drive the vehicle under its own power.
A feature common to all automobile alarm systems is the ability to selectively arm or disarm the system. A simple alarm system is armed after a prescribed time delay, such as 15 seconds, following the manual setting of an arming switch inside of the vehicle. (Typically, such switch is "hidden" or otherwise made non-conspicuous so that only the vehicle's owner knows of its location and function.) Once armed, all of the systems sensors are enabled and any entry or tampering event is interpreted as an unauthorized event or violation. The prescribed time delay subsequent to the arming of the system allows the vehicle owner sufficient time to exit the vehicle prior to the system becoming "armed". Similarly, upon reentering the vehicle, as mentioned above, another time delay allows the owner sufficient time to manually disarm the system before the alarm is sounded.
A major concern with existing automobile alarm systems relates to their cost, complexity of installation, and ease of maintenance verses their performance. To illustrate, a simple automobile alarm system (e.g., one that uses only the existing wiring of the automobile to sense the opening of a door and that sounds an alarm when unauthorized entry is detected) can be inexpensively manufactured and simple to install (and therefore quite affordable to the owner). Unfortunately, such a simple alarm system does not suit the needs, nor provide adequate protection, for many automobile owners. Therefore, most owners who want an alarm system will choose an alarm system that provides more protection and better suits their particular needs and vehicle.
Another concern associated with automobile and other type of alarm systems, e.g., house alarm systems, is that the sensors are designed to sense only a violation event that has already occurred, which event could (and usually does) involve some type of damage to the secured object, such as the breaking of a lock or the breaking of a windshield or other window glass. Thus, while the violation event is advantageously sensed by the alarm system, and the alarm is triggered by such event (which triggering of the alarm may scare the would-be intruder away from the area and/or signal others of the violation event), the violation event disadvantageously may cause damage or harm to the object being protected that must be repaired. What is needed, therefore, is an alarm system that not only senses a violation event, but that also detects when a violation event is about to occur so that a preliminary warning signal can be given in an attempt to protect against a would-be intrusion and prevent any damage before it occurs.
Because every application of an alarm system is somewhat unique, just as every make and model of automobile is somewhat different, and further because every owner of an alarm system is also different, and further because the needs of every owner change as a function of time and situation, there is no known universal alarm system, e.g., an automobile alarm system, that will suit the diverse needs of all owners at all times. Therefore, an owner must carefully shop around and try to select the alarm system that provides the best compromise given the owner's particular desires, needs and budget. See, e.g., "Auto Alarm Systems," Consumer Reports, October 1986, pp. 658-62. If the owner's needs or wants subsequently change, the only option available to the owner is to replace or upgrade the existing system with a new one that satisfies these new needs or wants. Such replacement and/or upgrading can be very bothersome and expensive, and in many situations is not practical.
Hence, what is needed, is a universal alarm system that can be efficiently and inexpensively manufactured, readily customized at installation to suit the particular needs of a particular owner, and easily modified thereafter to alter its performance. Such an alarm system can be used to protect an automobile, motorcycle, house, parking space, driveway or any other item of personal or real property, either by itself or in combination with existing alarm systems. Moreover, such an alarm system will include means for detecting not only a violation event (unauthorized entry or touching), but also an unauthorized approach towards the object or zone being protected.